Timer with reversible motor



April 23, 1963 c. SWENSON TIMER WITH REVERSIBLE MOTOR Filed Sept. 26,1961 2 Sheets-Sheet 2 FACTORS INVENTOR United States Patent 3,087,103TIMER WITH REVERSIBLE MOTOR Charles Swenson, P.0. Box 83, Madison SquareStation, New York 10, N.Y. Filed Sept. 26, 1961, Ser. No. 140,720 19Claims. (Cl. 318265) My invention relates to improvements in electrictimers, in which a motor running at constant speed controls energizingat electro receptive devices, as well as to such timers wherein themotor itself supplies motive power to machines while timing theiroperation.

This application is a continuation-impart of. my application Serial No.842,745, filed September 28, 1959, now abandoned.

It is an object of my improvements to provide a reliable and versatileinterval timer without using a great many different component parts asin existing devices of this kind, but so use instead a reversible motorcombined with a minimum number of readily available parts comprising: amotor driven member, a member for setting on a dial :at varyingdistances from the starting position of the motor driven member,together with switches to start the motor in one direction, to reversethe direction when the motor driven member meets the setting member, andso finally turn off the motor, when the motor driven member returns tothe starting position.

While I believe my improvements may be useful in other fields, asalready stated, I have illustrated in the accompanying drawings aninterval timer designed in accordance with my invention with an eye onphotography to control the duration of operation of external appliancessuch as lamps within a range of 1 minute, the dial being graduated inseconds from 1 to 60.

While continuous cycle repeating may be efi'ected by a twist of thestarting button, it is also an object of my improvements to provide acycle repeating mechanism for the simple timer to automatically extendthe controlled running time of the motor corresponding to the reading onthe dial multiplied by factors for example 2-30, as in an illustratedcase, thereby increasing the capacity of the timer in this case tomeasure intervals from 1 second to /2 hour.

Other objects and advantages of my improvements will appear with thereading of the specification.

Several simple embodiments of the timer have been illustrated diiieringmainly in the type of switch used to determine the running direction ofthe motor and the electrical circuit. One embodiment (FIGS. 1 and 2)employs two momentary, normally open switches, one of which as shown isstationary, but may also be carried by the motor driven member, whilethe other is carried by the setting member as shown, in FIGS. 4 and 5,only one momentary, normally open switch is used to reverse the motorwhile running in either direction; in another simple embodiment a singlepole double throw switch is carried by the motor driven member (FIG. 3),but may also be stationary as shown in FIGS. 12 and 13.

In the drawings FIG. 1 is a top view of the timer with the upper partremoved; FIG. 2 is a side view thereof partly in section showing theentire mechanism including the motor; FIGS. 3 and 4 are top views ofpart of the mechanism, and FIG. 5 a side view of FIG. 4; FIGS. 6 and 7are circuit diagrams, FIG. 7 to be read with the portion of FIG. 6 tothe left of the letters x; FIG. 8 is atop view of the timer with cyclerepeating mechanism; FIG. 9 is a top view of the cycle repeatingmechanism taken substantially on the plane 99 in FIG. 10, and FIG. 10 aside view thereof on the plane lit-10 in FIG. 9; FIG. 11 is an enlargedview of a modified cycle repeating mechanism; FIG. 12 shows anothermodification of,

"ice

the timer and cycle repeating mechanism, and FIG. 13 is a side view ofFIG. 12.

The same numerals reier to the same parts in all the views.

Describing first the simple embodiment shown in FIGS. 1 and 2, analternating cur-rent 1 rpm. motor 1 with gear box 2, output shaft 3,coils 4, 5, 6, 7 and tour pole pieces 8 is suspended by its case 9 onfour spacers 10 and fastened with screws "11 between a bottom plate 12and a mounting plate 13; a dial plate 14 is fastened to an enclosingwall 15, the latter being in turn mounted on the bottom plate, allplates 12-14 are of the same shape with a semi-circular part, the centerof which marks the axis of the motor, and the motor output shaft 3extends upward through the mounting plate 13. The dial plate 14 isprovided with a dial 16 (FIG. 8) graduated in seconds from 1-6G alongthe periphery of its semi-circular part. A motor arm 17 is secured tothe motor output shaft by screw 18 passed through a split hub section(FIG. 9) and carries a leaf spring 19 to act on a push button 20 on amain switch 21 to turn oil the latter, when the motor arm is in thestarting position, in which it is shown in the drawing. The main switchis a single pole single throw micro switch with a capacity to handlecurrent c0nsurned by the external appliances to be placed in parallelcircuit with the motor; it is secured to the mounting plate 13 withscrews 22 and has two push buttons 20, 23 protruding from opposite sidesof the switch casing, whereby the switch may be turned oil andonrespectively by a light pressure, one push button being in, when theother is out and vice versa. A smaller second switch 24 is fiastened onthe main switch with screws 25, its push button 26 aligned verticallywith the on push button 23 on the main switch. The switch 24 is amomentary, normal-ly open micro switch that, when actuated simultaneously with the main switch, will start the motor in a direction tomove the motor arm away from its starting position. A switch actuator 27has a cylindrical part 28 extending upward through the dial plate 14 andending in a starting button 29, a conical part 30 and a cylindrical part31 of reduced diameter, the latter provided with a flange 32 andextending downward through the mounting plate 13. The actuator 27 isurged upward by a coil spring 33 acting between the plate 13 and flange32, the movement being limited by a pin 34 passed through its lower end.A leaf spring 35 is held under the main switch to touch with one sidethe push buttons 23, 26 of the main switch 21 and the momentary switch24 respectively and provided with a roller 36 extending from the otherside and placed at tangent to the conical part 30 of the actuator 27.When a momentary pressure is applied to the starting button 29, the twoswitches 21, 24 will be actuated together causing instant start of themotor; the momentary switch returns at once to its normal off condition,while the main switch remains closed until opened by the leaf spring 19,when the motor arm returns to the starting position. A bushing 37 isprovided centrally in the dial plate 14 as a bearing for a stud 38 of asetting arm 39, which is held in place and under suitable tension bymeans of a spring washer 40 and a retaining ring 41; the stud 38 extendsupward through the bushing 37, above which a pointer 42 is attached witha set screw; the pointer is adapted for manual rotation over the dial 16and for setting thereon having a radial index edge 43. A third switch 44identi cal with the switch 24 is attached to the underside of thesetting arm 39 by screws 45, and an upright actuator 46 is fixed on themotor arm. to meet the push button 47 on the switch 44 and cause instantreversal of the motor and completion of the cycle after the exact timeperiod indicated by the pointer 42 on the dial 16. A phase splittingcapacitor 48 is mounted on the bottom. plate 12 to be included in thecircuit; also included is a receptacle 49 for external appliances, whichmay be [turned on or off independently of the motor or placed inparallel circuit therewith by means of a toggle switch 50 mounted on thedial plate 14. The receptacle is in the wall 15- together with a grummet 51 for an electric cord (not shown) with plug 52 for A.C. 60 c. lineoutlets. The electrical circuit for this embodiment may be convenientlyfollowed in FIG. 6 wherein, as in the diagram in FIG. 7 the symbols aregiven the same reference numerals as the parts they represent.

Turning now to the simple embodiment illustrated in FIG. 3 withelectrical diagram in FIG. 7 it is only necessary to point out, how itdiffers in construction and function from that already described. Amotor arm 53 is fastened to the motor output shaft 3 in the same manneras the motor arm 17, it carries a single pole double throw microswitchS4 with a pushbutton 55, 56 protruding substantially in the direction ofrotation from opposite sides of the switch casing. Depression by a lighttouch of a pushbutton throws the switch and determines the direction ofrotation of the motor arm 53 respectively toward and away from a settingarm 57, one pushbutton being in, when the other is out and vice versa.The setting arm 57 is practically similar to the setting arm 39, butcarries an upright actuator 58 to meet the pushbutton 56 and throw theswitch 54, so as to cause instant reversal of the motor and return ofthe motor arm to the starting position. A leaf spring 59 is furnished onthe main switch 21 to touch its pushbutton 2d and may be bent tofacilitate opening of the switch, it is designed to meet the pushbutton55 on the switch 54 and to open the main switch, as the motor armreturns to the starting position. Conversely closing of the main switchwill cause the spring 59 to throw the switch 54 and start the cycle. Thecylindrical part 28 of the switch actuator 27 is provided with a key 60,and the dial plate 14 with a keyway 61, whereby continuous running ofthe motor may be effected by a twist of the starting button 29, as themotor arm oscillates between its starting position and the setting arm57, until the actuator is released.

If the current carrying capacity of the double throw switch 54 permits,an extra receptacle may be connected between the condenser 48 and eitherside of the plug 52 (FIG. 7) so energise external appliances during oneselected half of the cycle. By rewiring the toggle switch 50 the sameresult may be obtained with the receptacle 49 in addition to the fullcycle energizing of the appliances.

In the construction just described two momentary, normally openmicroswitches may be carried by the motor arm for example in a commoncase like that of the switch 54 and connected in accordance with FIG. 6or FIG 7. While the double throw switch 54- must remain in the circuitduring the entire running time of the motor, the m0- mentary switchesneed only be connected at the start and reversal of the motor. In FIGS.4 and is illustrated an arrangement, whereby only one momentary switchis used, and carrying of wires by the motor arm is avoided. A momentary,normally open microswitch 62 is held to a part 63 of insulating materialof a motor arm by rivets 64, and a strip 65 of insulating material withtwo spaced apart flexible contact members 66 extending toward the motorarm is held under the main switch 21, so that electrical contact is madewith the rivets, as the motor arm nears the starting position. Likewisea strip 67 of insulating material with a pair of flexible contactmembers 68 is carried by the setting arm to contact the rivets 64, asthe motor arm meets the setting arm. The rivets are connected to theswitch terminals and the contact members to other electrical componentsto obtain the desired circuit.

Cycle Repeating The cycle repeating mechanism illustrated in FIGS.

8l0 and now to be described may be equally well installed in all thesimple embodiments of the timer, except where the momentary switch 24 isstationary and in the position shown in FIGS. 1 and 2, in which case anextra momentary switch is needed as described in my formally abandonedapplication Ser. No. 773,767, filed November 13, 1958.

The cycle repeating mechanism includes a vertical operating shaft 69with a bearing in a bracket 70, which is fastened to the underside ofthe dial plate 14 forming with the latter a housing for the mechanism.The shaft 69 extends upward through the dial plate and has a knob orpointer 71 attached to its extreme end by means of a set screw. A dial72 concentric with the operating shaft is provided on the plate 14 andhas equidistant graduations numbered clockwise from 230 to indicatecycle repeating factors by means of the pointer, and a stop 73 limitsmovement of the pointer to the factor 30 on the dial. A ratchet wheel 74and a spiral cam 75 are fastened together and keyed on the shaft 69, anda number of teeth have been removed from the ratchet wheel leaving acylindrical space 76 clear of teeth. A pawl 77 turning in the dial plateand the bracket 70 is biased by a light coil spring 78 held by an arm 79of the bracket 70 to follow the teeth of the ratchet wheel and permitclockwise rotation thereof, but prevent rotation in the other direction.A pin 80 is fixed upright in the motor arm and acts on the pawl 77 tobarely clear the teeth, when the motor arm is in the starting position;when the motor arm is in motion, and the cycle repeating mechanisminoperative, the pawl will rest on the body at the ratchet wheel in thetooth free space 76. The cam 75 is provided at the inner end of itsspiral rim with a recess 81, wherein rests a roller $2, when the cyclerepeating mechanism is inoperative. The roller 82 is carried in one endof a square rod 83, which slides in guides 84, part of the bracket 76,and carries in the other end a similar roller 85, which is in contactwith an inclined surface 86 cut in the switch actuator 27. If the knob71 is rotated clock-wise, the roller 82 leaves the recess 81 and followsthe spiral curvature of the cam 75, while the roller 85 will bearagainst the surface 86 and depress the actuator 27, thereby starting themotor. Conversely the upward force exerted by the spring '33 on theactuator will be transmitted to the spiral cam 75 to bias the latter forcounter clockwise rotation; if the knob 71 is set on a certain factor onthe dial 72, the cor-responding tooth, counting from the tooth freespace 76, will be engaged by the pawl 77. When the motor arm returns tothe starting position, the main switch cannot be turned off, instead thesecond switch (24, 54 or 62 as the case may be) is actuated, causinginstant reversal of the motor and start of a new cycle, while the pin 80acts on the pawl 77 to release a tooth on the ratchet wheel and engagethe next one, these actions being repeated until the mechanism hasreturned to the inoperative position.

The cycle repeating mechanism is best used to measure intervals over 1minute. The time is expressed in seconds, land the number taken as theproduct of two convenient factors, one of which preferably the larger isused for setting on the main dial 16. The knob 71 is then turned to theother factor on the dial 72 to start the timer.

The modified cycle repeating mechanism shown in FIG. ,11 is used withthe simple embodiments of the timer like the mechanism described above.in FIG. 11 a ratchet wheel 87 with a tooth removed at 88 and a circularcam 89 with a recess 90 for the roller 82 are keyed together on therotatory operating shaft 6% counter clockwise rotation of the shaftbeing prevented by a leaf spring 91 fixed in the bracket 7 0 and actingagainst radial faces of the ratchet teeth. A lever 92 for turning theratchet wheel a limited angle has hearings in the bracket 70 and thedial plate 14, one arm of the lever 92 forming a housing for a pivotedtongue 93 provided with a light leaf spring 94 to act against an innersurface of the housing to turn the tongue into position for engagementwith the ratchet wheel. The other lever arm 95 is engaged by the pin 80-carried on the motor arm, when the latter is in or near its startingposition and rests, when out of engagement with the pin against a stop96 on the bracket 70, toward which position it is biased by a coilspring 97 held by the bracket. The motor arm is shown in the startingposition, and the cycle repeating mechanism is in the inoperativeposition. When the operating shaft is rotated into a desired position,the movement of the roller 82 out of the recess 90 in the cam 89 willcause closing of the main switch 21, and the switch cannot be turnedoff, as long as the roller is on the circular rim of the cam. As themotor starts, the pin 80 leaves the position shown and is followed up bythe lever arm 95 as far as the stop 96, while the tongue 93 turns on itspivot to clear the ratchet teeth, the lever 92 now being in the positionindicated by the dotted lines. When the motor arm returns to itsstarting position, the pin 80 again engages the arm 95 and replaces thelever into its original position, while the tongue 93- advances theratchet wheel one pitch clockwise, this action being repeated until theroller 82 enters the recess 90. The tooth is removed from the ratchetwheel, so that the main switch may be closed for single cycle timingwithout operating the cycle repeating mechanism.

In FIGS. 12 and U3 a rod 98 for coupling to the output shaft of a motor(not shown) by means of a sleeve 99 has bearings in two supports 100,between which it is screw threaded for a member 101 adapted for axialmovement on the rod, as the latter rotates. The motor driven member 101carries a leaf spring 102 to act on the push button 20 on the mainswitch 21 to turn off the switch in the starting position of the motordriven member, in which position it is shown. A stationary single poledouble throw switch '103 has its operating member placed between twopins 104 on a switch actuator 105, which is movable lengthwise in thesupports 100, the movement being limited by stops 106 to that requiredto throw the switch, and one end of the motor driven member is suitablycut at 107 so as to be guided in its movement by the actuator. A member108 slides on the actuator for setting thereon at any distance from thestarting position of the motor driven member by means of a set screw 109and is provided with a roller 110 on its lower end to facilitate itsmovement and prevent sagging of the actuator. The electrical connectionin FIG. 7 is used so that when the main switch 21 is closed bydepressing its push button 23, the motor driven member first movesagainst a pin 111 on the actuator 105 and, as the spring 102 bends,throws the switch 103 for reversal and then moves toward the settingmember 108, where the switch is thrown again, and the motor drivenmember returns to the starting position opening the main switch. Ifdesired the motor may be reversed at any time while running by manualaction on the setting member 108 to throw the switch 103.

The cycle repeating mechanism consists of an operating member 112 ofrectangular cross section supported for lengthwise movement by means ofa handle 113 in two brackets 114 and biased toward the position shown,in which the cycle repeating mechanism is inoperative, by an extensionspring 115, the operating member 112 is provided with ratchet teeth fora pawl 116 sliding in two brackets 117 and biased to engage the teeth bya light coil spring 118, so that the member 112 may be latched in anumber of positions to operate the mechanism, and the timer is startedby closing the main switch. In the inoperative or zero position of thecycle repeating mechanism the pawl 116 barely clears a slightprotuberance 119 on the motor driven member 101, as the latter passes inits movement on the threaded rod 98 however, when the pawl 116 engages aratchet tooth, it is in the way and will be displaced in passing of themotor driven member, thereby releasing the operating member 112, whichtakes the next position closer to the zero position. A lever 120 pivotedon the main switch 21 has one arm urged by a light coil spring 121 intoa notch 122 in the operating members, when the latter is in the zeroposition, while the other arm lies behind the spring 102 withoutinterfering with opening of the main switch, but out of the notch thelever prevents opening of the switch, and the motor driven members, whenreturning to the starting position, will throw the switch 103 forreversal and start a new cycle.

The momentary or double throw reversing switch and each type of cyclerepeating mechanism described may be used substantially in the samemanner in combination with a straight moving motor driven member as witha rotating member (motor arm).

Two single throw switches with their operating members connected, sothat one switch is on, when the other is off and vice versa, may be usedin place of the double throw switch and are considered to be itsequivalent.

While I have described several embodiments of my improvements, it isunderstood, that changes may be made therein within the spirit of theinvention and scope of the following claims:

1. In a timing device: an electrically reversible motor responsive to amomentary circuit change by start in one direction or the other andreversal of direction while running in either direction; a member drivenby said motor and adapted for limited movement at constant-speed from astarting position; a member for setting in the path of said motor drivenmember at varying distances from said starting position; a main firstswitch to selectively energize and deenergize the motor circuit, amomentary, normally open second switch, and a momentary normally openthird switch connected in the circuit to effect by momentary closingaforesaid circuit change and thereby determine the direction of movementof the motor driven member; actuating means to close said main switchand momentarily close said second switch in the starting position of themotor driven member for movement thereof toward the setting member;means applying said movement to momentarily close said third switch forreversal of the motor at a position determined by the setting member,and means opening the main switch upon return to the starting positionof the motor driven member.

2. In a timing device according to claim 1, releasable means to preventopening of the main switch and effect automatic actuation of the secondswitch to reverse the motor and start a new cycle, as the motor drivenmember returns to the starting position.

3. In a timing device according to claim 1, means applying the inertiaof the motor driven member to close said momentary second switch in thestarting position after opening of the main switch, and until the latterswitch is again closed.

4. A timing device in accordance with claim 1, wherein only onemomentary, normally open switch is used, including means adapting saidswitch for actuation to run the motor in either direction, and meansdisconnecting the switch from the circuit between actuations.

S. In a timing device according to claim 4, releasable means to preventopening of the main switch and effect automatic actuation of themomentary switch to reverse the motor and start a new cycle, as themotor driven member returns to the starting position.

6. In a timing device according to claim 4, means applying the inertiaof the motor driven member to close said momentary switch in thestarting position after opening of the main switch, and until the latterswitch is again closed.

7. In a timing device: an electrically reversible motor responsive to acircuit change by start in one direction or the other and reversal ofdirection while running in either direction; a member driven by saidmotor and adapted for limited movement at constant speed from a startingposition; a member for setting in the path of said motor driven memberat varying distances from said starting position; a main first switch toselectively energize and deenergize the motor circuit; a double throwsecond switch connected in the circuit to effect when thrown aforesaidcircuit change and thereby determine the direction of movement of saidmotor driven member; actuating means to close said main switch and throwsaid second switch in the starting position of the motor driven memberfor movement thereof toward the setting member; means applying saidmovement to throw the second switch for reversal at a positiondetermined by the setting member, and means opening the main switch uponreturn to the starting position of the motor driven member.

8. In a timing device according to claim 7, releasable means to preventopening of the main switch and effect automatic throwing of the secondswitch to reverse the motor and start a new cycle, as the motor drivenmember returns to the starting position.

9. In a timing device according to claim 7, means applying the inertiaof the motor driven member to throw the second switch in the startingposition after opening of the main switch for movement toward thesetting member of the motor driven member, when the main switch is againclosed.

10. In a timing device according to claim 7, means throwing the secondswitch in the starting position for movement of the motor driven membertoward the setting member by movement away from the setting member.

11. In a timing device: an electrically reversible motor;

a member adapted for movement at constant speed transmitted by saidmotor in opposite directions between a starting position and a terminalposition; a main switch to selectively open and close the motor circuit;reversing switch means connected in the circuit and adapted foractuation in said starting position to start the motor and in eitheraforesaid position vby approaching movement of the motor driven memberto reverse the motor while running; a cycle repeating control mechanismincluding: an operating member biased toward a zero position, in whichsaid mechanism is inoperative; means to indicate cycle repeatingfactors; means for latching the operating member in positionscorresponding to said factors; means to prevent opening of the mainswitch, while the operating member is away from the zero position, andmeans associated with the motion driven member, acting withinconsecutive cycles, to release the operating member and cause it to takethe position corresponding to the next lower factor, until it hasreturned to the zero position.

12. In a timing device: an electrically reversible motor; a memberadapted for movement at constant speed transmitted by said motor inopposite directions between a starting position and a terminal position;a main switch to selectively open and close the motor circuit; reversingswitch means connected in the circuit and adapted for actuation in saidstarting position to start the motor and in either aforesaid position byapproaching movement of the motor driven member to reverse the motorwhile running; a cycle repeating control mechanism including: anoperating member having a zero position, in which said mechanism isinoperative; mean for setting the operating member in a plurality ofpositions; means to prevent opening of the main switch, while theoperating member is away from the zero position, and means associatedwith the motor driven member, acting at regular intervals, to cause theoperating member to take a position closer to the zero position, untilit has returned to that position.

13. A timing device according to claim 11, wherein the cycle to berepeated is of Variable duration, said terminal position beingdetermined by a member adapted for setting in the path of the motordriven member and at varying distances from the starting position.

14. A timing device according to claim 12, wherein the cycle to berepeated is of variable duration, said terminal position beingdetermined by a member adapted for setting in the path of the motordriven member and at varying distances from the starting position.

15. In a timing device according to claim 11, means to automaticallyclose the main switch, when the operating member is displaced from thezero position.

16. In a timing device according to claim 12, means to automaticallyclose the main switch, when the operating member is displaced from thezero position.

17. In a timing device according to claim 13, means to automaticallyclose the main switch, when the operating member is displaced from thezero position.

18. In a timing device according to claim 14, means to automaticallyclose the main switch, when the operating member is displaced from thezero position.

19. In a timing device an electrically reversible motor responsive to amomentary circuit change by start in one direction or the other andreversal of direction while running in either direction; a member drivenby said motor and adapted for movement at constant speed between astarting position and a terminal position; a member for setting in thepath of said motor driven member at varying distances from the startingposition to determine said terminal position; means to selectivelyenergize and deenergise the motor circuit, and secondary contact meansto make said momentary circuit change in the starting position to startthe motor and in either aforesaid position by approaching movement ofthe motor driven member to reverse the motor while running.

No references cited.

1. IN A TIMING DEVICE: AN ELECTRICALLY REVERSIBLE MOTOR RESPONSIVE TO AMOMENTARY CIRCUIT CHANGE BY START IN ONE DIRECTION OR THE OTHER ANDREVERSAL OF DIRECTION WHILE RUNNING IN EITHER DIRECTION; A MEMBER DRIVENBY SAID MOTOR AND ADAPTED FOR LIMITED MOVEMENT AT CONSTANT-SPEED FROM ASTARTING POSITION; A MEMBER FOR SETTING IN THE PATH OF SAID MOTOR DRIVENMEMBER AT VARYING DISTANCES FROM SAID STARTING POSITION; A MAIN FIRSTSWITCH TO SELECTIVELY ENERGIZE AND DEENERGIZE THE MOTOR CIRCUIT, AMOMENTARY, NORMALLY OPEN SECOND SWITCH, AND A MOMENTARY NORMALLY OPENTHIRD SWITCH CONNECTED IN THE CIRCUIT TO EFFECT BY MOMENTARY CLOSINGAFORESAID CIRCUIT CHANGE AND THEREBY DETERMINE THE DIRECTION OF MOVEMENTOF THE MOTOR DRIVEN MEMBER; ACTUATING MEANS TO CLOSE SAID MAIN SWITCHAND MOMENTARILY CLOSE SAID SECOND SWITCH IN THE STARTING POSITION OF THEMOTOR DRIVEN MEMBER FOR MOVEMENT THEREOF TOWARD